This is an extremely frequently asked question
your application should NOT need to have the user log out on close and the browsers are notoriously not telling you when they close
IE can be detected with

I annotated my article on ransomware somewhat extensively, but I keep adding new references and wanted to put a link to the reference library. Despite all the reference tools I have on hand, it was not easy to find a way to do this easily. I finall…

Nothing in an HTTP request can be trusted, including HTTP headers and form data. A form token is a tool that can be used to guard against request forgeries (CSRF). This article shows an improved approach to form tokens, making it more difficult to…

Learn how to match and substitute tagged data using PHP regular expressions. Demonstrated on Windows 7, but also applies to other operating systems. Demonstrated technique applies to PHP (all versions) and Firefox, but very similar techniques will w…